struct SDeferredDecal {
  Matrix34 projMatrix;
  IMaterial * pMaterial;
  float fAlpha;
  float fGrowAlphaRef;
  RectF rectTexture;
  uint32 nFlags;
  uint8 nSortOrder;
};

IShader.h

float fAlpha;

transparency of decal, used mostly for distance fading

float fGrowAlphaRef;

uint32 nFlags;

uint8 nSortOrder;

user defined sort order

IMaterial * pMaterial;

decal material

Matrix34 projMatrix;

defines where projection should be applied in the world

RectF rectTexture;

subset of texture to render

SDeferredDecal();